import 'package:flutter/material.dart';

class Echo extends StatelessWidget {
  final String text;
  final Color backgroundColor;

  const Echo({Key? key, required this.text, this.backgroundColor = Colors.blue})
    : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Center(child: Container(color: backgroundColor, child: Text(text)));
  }
}

class StatelessExample extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Stateless Widget Example',
      home: Scaffold(
        appBar: AppBar(title: Text('Stateless Widget')),
        body: Echo(text: 'Hello Flutter!', backgroundColor: Colors.green),
      ),
    );
  }
}
